Revolver cylinder pin and cross pin



Oct. 11, 1960 w. B. RUGER REVOLVER CYLINDER PIN AND CROSS PIN FiledApril 10, 1959 FIG. I

Patented Oct. 11, 1960 Lin REVOLVER CYLINDER PIN AND CROSS PIN WilliamB. Ruger, Southport, Conn., assignor to Sturm, Ruger and Company, Inc,Southport, Conn, a corporation of Connecticut Filed Apr. 10, 1959, Ser.No. 805,573

1 Claim. or. 42-59 This invention relates to revolvers of the typehaving the cylinder mounted on a removable pin which is inserted fromthe forward end into a hole in the frame in which it makes bearingcontact, and has for its object the provision of certain improvements inrevolvers of this type. The well known Colt Frontier model and theimproved Ruger are revolvers of the type with which the invention isprimarily concerned.

The cylinder pin on which the cylinder is mounted is removably held inposition by the cross-pin of a latch in the forward part of the framethat makes engagement with an annular groove in the cylinder pin. Thecrosspin actually is a spring-pressed plunger which can be pressed outof latching position to release the cylinder pin, and because of thelimited space, the cross-pin makes only a line contact with the groove.Recently these revolvers have been made for the powerful 44 Magnumcartridge which results in a violent recoil not known with the smallercalibers. As a result of this recoil and the small area of contact ofthe cross-pin with the groove the cross-pins have been pushed outwardagainst the spring releasing the cylinder pin.

This invention overcomes the aforementioned drawbacks by providing animproved cylinder pin that cannot be released without actuallydepressing the cross-pin. My improved cylinder pin comprises atransverse groove, preferably arcuate, in which the cross-pin makescontact, and an enlarged head on the forward end having an arcuate outwhich makes contact with the under surface of the barrel which is solocated with respect to the groove that the cylinder pin can be insertedinto the frame in only one position with the transverse groove always ina position coincident with the cross-pin. The transverse groove providessuch long surface contact with the crosspin that it cannot be displacedaccidentally as a result of recoil.

In the accompanying drawings:

Fig. 1 is a side view of a revolver embodying the invention with partsremoved;

Fig. 2 is an enlarged fragmentary sectional view taken at 2-2 of Fig. 3;

Fig. 3 is an enlarged sectional view taken at 3-3 of Fig. 1;

Fig. 4 is an enlarged sectional view taken at 44 of Fig. 1; and

Fig. 5 is a perspective of the cylinder pin.

The revolver illustrated in the drawings comprises a frame 1, a barrel 2and a grip member 3'. It is to be understood that this may be a revolversimilar in its construction and action to the old Colt Frontier model orthe currently produced Ruger model. It is a single action revolverhaving its cylinder 4 rotatably mounted on the cylinder pin 5 which isinserted from the forward end through a hole 6 in the forward part ofthe frame, through the cylinder, and into a hole 7 in the rearwardportion of the frame.

The empty cases are ejected from the cylinder by means of a rod 8 whichis mounted in the housing 9 attached to one side of the barrel. This rodis operated in the well known manner by pressing it into the cylinderagainst the action of the spring '10 which returns it to its inactiveposition.

As best shown in Fig. 5 the cylinder pin 5 has a transverse notch orgroove 12 which assumes a position coincident with the hole 13 in theforward portion of the frame. In this hole a spring opposed latchingmember 14 is mounted. This latching member comprises a crosspin 15having a centrally tapped hole in which the threaded end of theoperating head 16 is in threaded engagement. As shown in the drawings,the cross-pin 15 is in latching engagement with the cylinder pin. Itwill be noted with reference to Fig. 4 that the hole 13 comprises aninner annular shoulder 17 against which the cross-pin 15 makesengagement on one side and the coil spring 18 surrounding the innerportion of member 16 makes bearing contact on the opposite side. Inorder to release the cross-pin 15 from its latching engagement with thenotch 12 one merely pushes the member 16 inwardly or towards the left,as shown in Fig. 4, against the action of spring 18, until the cross-pinis removed from the notch 12. When this is done one can then slide thecylinder pin forward sufficiently to remove it from the cylinder therebymaking it possible to remove the cylinder from the frame 1.

In order that the notch 12 shall alwaysassume the proper position in theframe for the insertion therein of cross-pin 15, a collar or shoulder20, preferably integral with the cross-pin, is provided. This collar hasan arcuate cut 21 having the approximate shape of the cylinder barrel.In inserting the cylinder pin into the frame it is necessary to hold itin such position that the arcuate cut 21 slides along the under surfaceof the barrel which guides it. It is impossible, therefore, to insertthe cylinder pin into the frame and cylinder so that the notch 12 willnot be in position to receive the cross-pin 15.

The annular grooves 22 on the forward end of the cylinder pin are merelyfor the purpose of effecting a better grip.

It will be noted with reference to Fig. 4 that because of the annularshoulder 17 there is not sufiicient space in the narrow area of theforward part of the frame to provide a spring opposed latching cross-pinthat can extend across the entire width of the notch 12. It is becauseof this limitation of space that when the annular groove in thecross-pin as used heretofore is provided there is only a line contactbetween the cross-pin and the groove, and this line contact is made, at,or near, the center line of pin 5. If, because of dirt or tolerances inmanufacturing, the cross-pin 15 does not reach the center line of 5,and, when the gun recoils violently, as with modern high powerammunition, there is a lateral component force set up which causes thecylinder pin to force the cross-pin out of engagement. With the presentinvention the position of the cross-pin is not critical and if the endof pin 15 does not go beyond the center line of 5, it will hold anyway.As shown in Fig. 4 this is not possible because of the substantial areaof contact between the cross-pin and the notch 12.

I claim:

In revolvers of the type having a frame, a cylinder mounted in theframe, a barrel attached to the frame, a cylinder pin on which thecylinder rotates inserted through a hole in the front of the framethrough the cylinder and into a bearing hole in the rear of the frame, across-pin mounted in a hole in the front part of the frame that engagesmeans in the cylinder pin to hold the cylinder pin in secured butreleasable position, the improvement which comprises a transverse notchon one side of the cylinder pin into which the cross-pin makes latchingengagement, said transverse notch being a cylindrical segment and saidcross-pin having a cylindricalnotch engaging portion, a shoulder on thecylinder pin forward of the notch having an arcuate cut in the longilocate the transverse notch in proper position for the insertion of thecross-pin.

References Cited in the file of this patent UNITED STATES PATENTS519,875 Rourke May 15, 1895 884,119 Zaiser Apr. 7, 1908 2,806,316 RugerSept. 17,1957

